Hydration delivery system for stents

ABSTRACT

A stent delivery device is provided that includes an inner member defining a distal tip and a stent holding region, and an outer tubular member slidingly disposed over the inner member and configured to engage the distal tip. Seal members may be disposed on one or more of an outer surface of the inner member, the distal tip, and the outer tubular member. The seal members define a liquid-tight sealed chamber surrounding the stent holding region.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.15/852,716, filed Dec. 22, 2017, which claims priority to U.S.Provisional Application Ser. No. 62/440,245, filed Dec. 29, 2016, theentirety of which is incorporated herein by reference.

TECHNICAL FIELD

The disclosure is directed to devices and methods for loading,transporting, and delivering stents. More particularly, the disclosureis directed to methods and systems for loading and delivering radiallydistensible stents in a liquid environment.

BACKGROUND

An intraluminary prosthesis is a medical device used in the treatment ofdiseased bodily lumens. One type of intraluminary prosthesis used in therepair and/or treatment of diseases in various body lumens is a stent. Astent is generally a longitudinal tubular device formed of biocompatiblematerial which is useful to open and support various lumens in the body.For example, stents may be used in a bodily lumen, such as in thecoronary or peripheral vasculature, esophagus, trachea, bronchi, colon,biliary tract, urinary tract, prostate, brain, as well as in a varietyof other applications in the body. These devices are implanted withinthe body lumen to open and/or reinforce collapsing or partially occludedsections of the lumen.

Stents generally include an open flexible configuration. Thisconfiguration allows the stent to be inserted through curved bodylumens. Furthermore, this configuration allows the stent to beconfigured in a radially compressed state for intraluminary catheterimplantation. Once properly positioned adjacent the damaged treatmentsite in the body lumen, the stent is radially expanded so as to supportand reinforce the body lumen. Radial expansion of the stent may beaccomplished by inflation of a balloon attached to the catheter or thestent may be of the self-expanding variety which will radially expandonce deployed and unconstrained. Tubular shaped structures, which havebeen used as intraluminary stents, have included helically wound coilswhich may have undulations or zig-zags therein, slotted stents, ringstents, braided stents and open mesh wire stents, to name a few.Super-elastic, metallic, and polymeric shape memory materials have beenused to form stents. Additionally, fully bioabsorbable stents and stentscoated with bioabsorbable materials such as bioelastomers have beenmade.

Although many stent delivery systems are well-known in the art, unlikemetallic and most polymer self-expanding stents, stents made withbioabsorbable materials and bioelastomers may require constant hydrationin order to retain their elastic properties. Also, tissue covered stentsmay require submersion in a liquid environment to maintain tissuehydration and health. Accordingly, there is a need for stent deliverysystems that provide a liquid environment for the stent duringtransportation and delivery.

BRIEF SUMMARY

This disclosure provides design, material, and use alternatives formedical devices, including delivery systems.

A first example includes a stent delivery device. The device includes aninner member having a distal tip and a stent holding region proximal ofthe distal tip. The device also includes an outer tubular memberslidingly disposed over the inner member. The outer tubular member has adistal end configured to engage the distal tip. The device also includesat least one first seal member disposed between the inner member and theouter tubular member proximal of the stent holding region, and at leastone second seal member disposed between the distal tip and the outertubular member. A combination of the first and second seal membersdefines a liquid-tight sealed chamber surrounding the stent holdingregion.

Alternatively or additionally to any of the above examples, the firstseal member is disposed on an outer surface of the inner member.

Alternatively or additionally to any of the above examples, the firstseal member is disposed on an inner surface of the outer tubular member.

Alternatively or additionally to any of the above examples, the secondseal member is disposed on the distal tip.

Alternatively or additionally to any of the above examples, the secondseal member is disposed on an inner surface of the distal end of theouter tubular member.

Alternatively or additionally to any of the above examples, the firstseal member includes two or more separate seal members spaced apartaround a circumference of the inner member.

Alternatively or additionally to any of the above examples, the firstseal member is an O-ring disposed on an outer surface of the innermember.

Alternatively or additionally to any of the above examples, the secondseal member includes two or more separate seal members spaced apartaround a circumference of the distal tip.

Alternatively or additionally to any of the above examples, the secondseal member includes a tapered region at the distal end of the outertubular member, such that a diameter of the outer tubular member at thedistal end is smaller than a diameter of the outer tubular memberproximal of the distal end.

Alternatively or additionally to any of the above examples, the secondseal member includes at least one circumferential protrusion disposed onan inner surface of the distal end of the outer tubular member.

Alternatively or additionally to any of the above examples, the distaltip includes a groove configured to receive the protrusion.

Alternatively or additionally to any of the above examples, the secondseal member includes a tapered region at the distal end of the outertubular member, such that a diameter of the outer tubular member at thedistal end is smaller than a diameter of the outer tubular memberproximal of the distal end, the second seal member further including atleast one protrusion disposed on an inner surface of the tapered regionat the distal end of the outer tubular member.

Alternatively or additionally to any of the above examples, the innermember includes a lumen with at least one port configured to deliverliquid to the chamber.

Alternatively or additionally to any of the above examples, the portincludes a plurality of ports extending from the lumen into the chamber,the plurality of ports disposed along the stent holding region.

Alternatively or additionally to any of the above examples, the lumenextends from a proximal region of the inner member to the port, whereinthe port is disposed proximal of the stent holding region.

Alternatively or additionally to any of the above examples, the devicefurther includes a tubular member disposed adjacent the inner member,the tubular member extending from a proximal region to a distal enddisposed within the chamber.

Alternatively or additionally to any of the above examples, the devicefurther includes a stent stopper disposed around the stent holdingregion at a proximal end of the chamber, wherein the stent stopperincludes an opening through which the tubular member extends.

Another example is a stent delivery device including an inner memberhaving a distal tip, a stent holding region, and at least one first sealmember disposed on an outer surface of the inner member proximal of thestent holding region. The device further includes an outer tubularmember slidingly disposed over the inner member. The outer tubularmember has a distal end configured to engage the distal tip. At leastone of the distal tip and the distal end of the outer tubular memberincludes at least one second seal member, wherein a combination of thefirst and second seal members defines a liquid-tight sealed chambersurrounding the stent holding region.

Alternatively or additionally to any of the above examples, the firstseal member includes two or more separate seal members spaced apartaround a circumference of the inner member, wherein the second sealmember includes at least one protrusion disposed on an inner surface ofthe distal end of the outer tubular member.

Another example is a method of loading a bioabsorbable stent, retainedin a liquid environment, into a delivery device. The method includesloading a bioabsorbable stent onto a stent holding region of a stentdelivery device. The stent delivery deice includes an inner memberhaving a distal tip, the stent holding region, a lumen, and at least onefirst seal member disposed on an outer surface of the inner member. Thestent delivery device also includes an outer tubular member slidinglydisposed over the inner member. The outer tubular member has a distalend configured to engage the distal tip. At least one of the distal tipand the outer tubular member includes at least one second seal member. Acombination of the first and second seal members seals the outer tubularmember to the inner member distal and proximal of the stent holdingregion. The method further includes sliding the outer tubular memberdistally over the bioabsorbable stent until the distal end of the outertubular member engages the distal tip, thereby forming a liquid-tightsealed chamber around the stent. The method further includes introducingliquid medium through the lumen in the inner member and into theliquid-tight sealed chamber to hydrate the stent.

The above summary of some embodiments is not intended to describe eachdisclosed embodiment or every implementation of the present disclosure.The Figures, and Detailed Description, which follow, more particularlyexemplify some of these embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings, which are not necessarily drawn to scale, like numeralsmay describe similar components in different views. The drawingsillustrate generally, by way of example, but not by way of limitation,various embodiments discussed in the present document.

FIG. 1 is a partial cross-sectional view of a stent delivery device inaccordance with an embodiment of the disclosure;

FIGS. 2A and 2B are close-up partial cross-sectional views of the distalregion of the stent delivery device showing examples of details of theinner member of the stent delivery device;

FIGS. 3A-3H are close-up partial cross-sectional views of the distalregion of the stent delivery device showing examples of details of thedistal tip of the stent delivery device;

FIGS. 4A-4C are close-up partial cross-sectional views of the distalregion of the stent delivery device showing examples of details of thedistal end of the stent delivery device; and

FIGS. 5A-5C are close-up partial cross-sectional views of the distalregion of the stent delivery device showing examples of details of afluid pathway into the hydration chamber of the stent delivery device.

While the disclosure is amenable to various modifications andalternative forms, specifics thereof have been shown by way of examplein the drawings and will be described in detail. It should beunderstood, however, that the intention is not to limit the invention tothe particular embodiments described. On the contrary, the intention isto cover all modifications, equivalents, and alternatives falling withinthe spirit and scope of the disclosure.

DETAILED DESCRIPTION

For the following defined terms, these definitions shall be applied,unless a different definition is given in the claims or elsewhere inthis specification. Definitions of certain terms are provided below andshall be applied, unless a different definition is given in the claimsor elsewhere in this specification.

All numeric values are herein assumed to be modified by the term“about”, whether or not explicitly indicated. The term “about” generallyrefers to a range of numbers that one of skill in the art would considerequivalent to the recited value (i.e., having the same function orresult). In many instances, the term “about” may be indicative asincluding numbers that are rounded to the nearest significant figure.The recitation of numerical ranges by endpoints includes all numberswithin that range (e.g., 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4,and 5).

Although some suitable dimensions, ranges and/or values pertaining tovarious components, features and/or specifications may be disclosed, oneof skill in the art, incited by the present disclosure, would understanddesired dimensions, ranges and/or values may deviate from thoseexpressly disclosed.

As used in this specification and the appended claims, the singularforms “a,” “an,” and “the” include or otherwise refer to singular aswell as plural referents, unless the content clearly dictates otherwise.As used in this specification and the appended claims, the term “or” isgenerally employed to include “and/or,” unless the content clearlydictates otherwise.

It is noted that references in the specification to “an embodiment”, “anexample”, “some embodiments”, “some examples”, “another embodiment”,“another example” etc., indicate that the embodiment or exampledescribed may include one or more particular features, structures,and/or characteristics. However, such recitations do not necessarilymean that all embodiments or examples include the particular features,structures, and/or characteristics. Additionally, when particularfeatures, structures, and/or characteristics are described in connectionwith one embodiment or example, it should be understood that suchfeatures, structures, and/or characteristics may also be used connectionwith other embodiments and examples whether or not explicitly describedunless clearly stated to the contrary.

References herein to the term “distal” and variants thereof refer to adirection away from an operator of the subject devices, while referencesto the term “proximal” and variants thereof refer to a direction towardsthe operator of the subject devices. Accordingly, when the terms“distal” and “proximal” are used herein in the context of an assemblydevice that is being deployed within a body, such as a human body, by anoperator, the term “distal” refers to a location within or near the bodythat is further within the body than a location that is “proximal” orcloser to the operator.

The following detailed description should be read with reference to thedrawings in which similar elements in different drawings are numberedthe same. The detailed description and the drawings, which are notnecessarily to scale, depict illustrative embodiments and are notintended to limit the scope of the disclosure. The illustrativeembodiments depicted are intended only as exemplary. Selected featuresof any illustrative embodiment may be incorporated into an additionalembodiment unless clearly stated to the contrary.

FIG. 1 is a cross-sectional view of a stent loading and delivery systemor device 10 according to the present invention. The device 10 isparticularly well suited for the loading, transluminal delivery andintraluminal deployment of a radially self-expanding prosthesis in aliquid environment, such as a bioabsorbable stent and/or a stent-graft,which may be radially compressed and loaded into device 10,transluminally delivered to an intended intraluminal treatment site,then released from the system for radial self-expansion againstsurrounding tissue. While the present device can be applied to thedelivery of many intraluminary devices, it is particularly suited fordelivering the self-expanding stent 60 while the stent 60 is immersed ina liquid environment. The stent 60 is capable of being radiallycompressed and longitudinally extended for delivery into a bodily lumen.The degree of elongation depends upon the structure and materials of thestent 60 and may be quite varied. The diameter of the stent 60 also maybecome several times smaller as it is radially compressed. The stent 60may be constructed to self-expand when unconstrained, and thus releasedfrom a radially compressed state to expand to a radially expanded state.Any stent that is capable of radial expansion may be used in accordancewith the present device. For example, a radially distensible stent whichdoes not substantially longitudinally elongate upon radial contractionis also useful. Various stent types and stent constructions may beemployed in the device 10, and the device 10 may be constructed toaccommodate stents of various sizes and configurations.

One example of the present device applies to a bioabsorbable stent 60.As used herein the term bioabsorbable and the related termsbiodegradable and bioresorbable, refer to the property of being capableof being absorbed or resorbed into living tissue, or degrading whendisposed in living tissue, such that the stent is cleared from the body,leaving no permanent implant. In some examples, a fully bioabsorbablestent is coated in a bioelastomer, and the resulting stent structurerequires constant hydration in order to retain its elastic properties.Another example includes a tissue covered stent for prophylactic healingafter esophageal resection or other injuries. Such a stent may requiresubmersion in media to maintain tissue hydration and health. It is notedthat in some instances, a only portion of stent 60 may be bioabsorbable,bioresorbable and/or biodegradable (e.g., a covering layer), while otherportions of stent 60 may be biostable. However, in other instances,stent 60 may be fully bioabsorbable, bioresorbable and/or biodegradable.

Useful and nonlimiting examples of bioabsorbable or biodegradablepolymeric materials from which a stent may be made includepoly(L-lactide) (PLLA), poly(D,L-lactide) (PLA), poly(glycolide) (PGA),poly(L-lactide-co-D,L-lactide) (PLLAIPLA), poly(L-lactide-co-glycolide)(PLLAIPGA), poly(D,L-lactide-co-glycolide) (PLAIPGA),poly(glycolide-co-trimethylene carbonate) (PGAIPTMC), polydioxanone(PDS), Polycaprolactone (PCL), polyhydroxybutyrate (PHBT),poly(phosphazene) poly(D,L-lactide-co-caprolactone) PLAIPCL),poly(glycolide-co-caprolactone) (PGA/PCL), poly(phosphate ester) and thelike. Further, the stent 60 may include materials made from or derivedfrom natural sources, such as, but not limited to collagen, elastin,glycosaminoglycan, fibronectin and laminin, keratin, alginate,combinations thereof and the like.

Further, the stent 60 may be made from bioabsorbable polymeric materialswhich may also include radiopaque materials, such as metallic-basedpowders or ceramic-based powders, particulates or pastes which may beincorporated into the polymeric material. For example, the radiopaquematerial may be blended with the polymer composition from which thepolymeric stent is formed, and subsequently fashioned into the stent asdescribed herein. Alternatively, the radiopaque material may be appliedto the surface of the stent. Various radiopaque materials and theirsalts and derivatives may be used including, without limitation,bismuth, barium and its salts such as barium sulfate, tantalum,tungsten, gold, platinum and titanium, to name a few. Additional usefulradiopaque materials may be found in U.S. Pat. No. 6,626,936, which isherein incorporated by reference in its entirety. The stent 60 may beselectively made radiopaque at desired areas along the stent or may befully radiopaque, depending on the desired end-product and application.

Also, the stent 60 may include coverings, films, coatings, and the likedisposed over, under or throughout or embedding an expandable scaffoldof the stent 60. For example, the stent 60 may include a covering, suchas a bioabsorbable polymeric covering, disposed over the longitudinallength or a portion of the longitudinal length of an expandable tubularscaffolding of the stent 60. Further, the stent 60 may include a liner,such as a bioabsorbable polymeric liner, disposed within thelongitudinal length or a portion of the longitudinal length of anexpandable tubular scaffolding of the stent 60. Moreover, the stent 60may include both a covering and a liner, such as a bioabsorbablepolymeric covering and liner which include the same or differentbioabsorbable polymeric materials, disposed over and within thelongitudinal length or a portion of the longitudinal length of anexpandable tubular scaffolding of the stent 60. The covering and/or theliner may be a unitary film or coating that embeds or partially embedsthe expandable tubular scaffold of the stent 60. In some instances, thecovering and/or liner may be applied to the tubular scaffold of thestent 60 in a dip coating or spray coating process. The bioabsorbablecovering and/or the liner may be in the form of a tubular structure, forexample composed of polymeric material and/or silicone. The coveringand/or the liner may be transparent or translucent, desirablysubstantially or partially transparent. Furthermore, the bioabsorbablecovering and/or the liner may be constructed of any suitablebioabsorbable materials as discussed above with regard to the stent 60.

In some examples, the stent 60 may be treated with a therapeutic agentor agents, such as, but not limited to, anti-thrombogenic agents (suchas heparin, heparin derivatives, urokinase, and PPack(dextrophenylalanine proline arginine chloromethylketone);anti-proliferative agents (such as enoxaprin, angiopeptin, or monoclonalantibodies capable of blocking smooth muscle cell proliferation,hirudin, and acetylsalicylic acid); anti-inflammatory agents (such asdexamethasone, prednisolone, corticosterone, budesonide, estrogen,sulfasalazine, and mesalamine);antineoplastic/antiproliferative/anti-miotic agents (such as paclitaxel,5-fluorouracil, cisplatin, vinblastine, vincristine, epothilones,endostatin, angiostatin and thymidine kinase inhibitors); anestheticagents (such as lidocaine, bupivacaine, and ropivacaine);anti-coagulants (such as D-Phe-Pro-Arg chloromethyl keton, an RGDpeptide-containing compound, heparin, antithrombin compounds, plateletreceptor antagonists, anti-thrombin antibodies, anti-platelet receptorantibodies, aspirin, prostaglandin inhibitors, platelet inhibitors andtick antiplatelet peptides); vascular cell growth promotors (such asgrowth factor inhibitors, growth factor receptor antagonists,transcriptional activators, and translational promotors); vascular cellgrowth inhibitors (such as growth factor inhibitors, growth factorreceptor antagonists, transcriptional repressors, translationalrepressors, replication inhibitors, inhibitory antibodies, antibodiesdirected against growth factors, bifunctional molecules consisting of agrowth factor and a cytotoxin, bifunctional molecules consisting of anantibody and a cytotoxin); cholesterol-lowering agents; vasodilatingagents; and agents which interfere with endogenous vascoactivemechanisms.

As shown in FIG. 1, the stent 60 may have a straight or substantiallystraight longitudinal configuration. The present disclosure, however, isnot so limited. For example, the stent 60 may have a varied diameter,such as a flaring or tapering, along a portion or portions of itslongitudinal expanse. One non-limiting example of a varied diameterstent is a stent having a longitudinal body and a flared end at thefirst and/or second end of the stent (not shown). Flared ends may have adiameter greater than the diameter of the longitudinal body of the stent60 between the flared ends. The stent 60, however, is not so limited,and for example flared ends, individually or in combination, may have asmaller diameter that the diameter of at least a portion of thelongitudinal body of the stent 60. Further, the stent 60 may berepositionable, removable and/or reconstrainable, and/or may includemultiple interconnected or non-interconnected stents.

As shown in FIG. 1, the device 10 may include an elongate catheter shaft12 extending distally from a handle assembly 14. The elongate cathetershaft 12 may include an elongate, flexible inner member 40 with a distaltip 30, disposed and slidable within the lumen of an outer tubularmember 20, interrelated as shown. The distal tip 30 is useful fornavigating bodily lumens without causing trauma to the same. In someinstances, the inner member 40 may be a tubular member defining a lumenextending therethrough. In some instances, the lumen of the inner member40 may extend through the distal tip 30 for navigation of the device 10over a guidewire, for example.

The proximal end of the outer tubular member 20 may be secured to afirst, distal handle 16 of the handle assembly 14 and the inner member40 may be secured to a second, proximal handle 18 of the handleassembly. The handle 16 may be actuated (e.g., longitudinally actuated)relative to the handle 18 in order to longitudinally actuate or move theouter tubular member 20 relative to the inner member 40.

The inner member 40 may include a stent holding region 41 at a distalend region thereof around which the stent 60 may be positioned in acompressed state. The stent holding region 41 may have a diametersmaller than the diameter of the inner member 40 proximal of the stentholding region 41. A shoulder 43 between the narrower stent holdingregion 41 and the wider proximal portion of the inner member 40 mayserve as a proximal stop preventing the stent 60 from moving proximallywhen the outer tubular member 20 is withdrawn proximally over the stent60. In other examples, a stent stopper 75 may be provided, as shown inFIG. 5C. The outer tubular member 20 is sized to slide over, orotherwise be positioned over and surround the constrained stent 60, andthus constrain or radially compress the stent 60 in a radiallyconstrained or compressed configuration, with the stent holding region41 of the inner member 40 extending through the lumen of the stent 60.The outer tubular member handle 16, which may be disposed at and fixedlysecured to the proximal end of the outer tubular member 20, may be usedto advance and retract the outer tubular member 20 over the stent 60.

In order to provide a liquid environment for the stent 60, a sealablechamber 25 for holding the stent 60 may be formed between the innersurface of the outer tubular member 20 and the outer surface of thestent holding region 41 of the inner member 40 along the longitudinalextent of the stent 60, such as between the distal tip 30 and theshoulder 43 of the inner member 40. The sealable chamber 25 may becreated by sealing members disposed on one or more of the distal tip 30,the inner member 40, and the outer tubular member 20. Water-tight sealsmay be created between the distal tip 30 and the distal end of the outertubular member 20 distal of the distal end of the stent 60, and betweenthe outer tubular member 20 and the inner member 40 proximal of theproximal end of the stent 60.

Features may be added to the outer surface of the inner member 40 and/orthe inner surface of the outer tubular member 20 to create a sealbetween the inner member 40 and the outer tubular member 20 at theproximal end of the chamber 25. Furthermore features may be added to theouter surface of the distal tip 30 and/or the inner surface of the outertubular member 20 to create a seal between the outer tubular member 20and the distal tip 30 at the distal end of the chamber 25. The featuresmay be discrete but circumferentially continuous around the inner member40, the outer tubular member 20 and/or the distal tip 30 in one or morerows, depending on the desired (or necessary) strength of the seal.FIGS. 2A-4C illustrate various examples of features that may be providedon one or more of the distal tip 30, inner member 40, and outer tubularmember 20 to provide a sealed chamber 25 in which the stent 60 resides.The stent 60 has been removed from FIGS. 2A-5C for clarity.

FIG. 2A illustrates a seal member 42 circumferentially surrounding theinner member. The seal member 42 is shown with angular surfaces. Theseal member 42 may be secured to the inner member 40 and/or formedintegrally with the inner member 40. In some examples, a plurality ofseal members may be disposed circumferentially around the inner member40 at spaced apart locations. FIG. 2B shows two continuous O-ring shapedseal members 44 that continuously surround the entire circumference ofthe inner member 40. The inner member 40 may have recessed grooves toaccommodate part of the thickness of the seal member 44 when the sealmember 44 is arranged in the recessed groove, or the seal member 44 maybe added on top of the inner member 40 with adhesive, for example.

When the outer tubular member 20 is advanced distally over the innermember 40, the seal members 42, 44 engage the inner surface of the outertubular member 20, forming a liquid-tight seal between the inner member40 and the outer tubular member 20. In some examples, the seal member42, 44 may be rigid, forming the seal based on a friction fit againstthe inner surface of the outer tubular member 20. In other examples, theseal members 42, 44 may be compressible, and may be compressed as theouter tubular member 20 is advanced distally over the seal members 42,44.

Similar to the seal members 42, 44 shown on the inner member 40 in FIGS.2A and 2B, seal members 50-57, shown in FIGS. 3A-3H, may be disposed onthe proximal portion 31 of the distal tip 30 that engages the innersurface of the outer tubular member 20. The addition of these sealmembers 50-57 may decrease the space between the proximal portion 31 ofthe distal tip 30 and the outer tubular member 20, forming aliquid-tight seal at the distal end of the chamber 25 and retainingliquid within the chamber 25. When the outer tubular member 20 isadvanced distally over the proximal portion 31 of the distal tip 30, oneor more of the seal members 50-57 may engage the inner surface of theouter tubular member 20, forming a liquid-tight seal between the distaltip 30 and the outer tubular member 20. In some examples, the sealmembers 50-57 may be rigid, forming the seal based on a friction fitagainst the inner surface of the outer tubular member 20. In otherexamples, the seal members 50-57 may be compressible, and may becompressed as the outer tubular member 20 is advanced distally over theproximal portion 31 of the distal tip 30.

The seal members 50-57 form a releasable friction seal against the innersurface of the outer tubular member 20. When the stent 60 is to bereleased, the outer tubular member 20 may be withdrawn proximally fromthe distal tip 30, releasing the seal and opening the liquid-tightchamber 25.

FIGS. 3A-3H illustrate various configurations and shapes of seal members50-57. For example, seal member 50 shown in FIG. 3A has a rounded outersurface, and the pair of seal members 51 positioned adjacent each othershown in FIG. 3B also include a rounded outer surface. Seal member 52,shown in FIG. 3C, is elongated and has a flat top and rounded sidesurfaces. Seal member 53, shown in FIG. 3D, has a polygonalcross-sectional shape with a flat top, while FIG. 3E illustrates a pairof seal members 54 adjacent one another with a polygonal cross-sectionalshape. The seal member 55, shown in FIG. 3F, has a triangular shape witha pointed tip configured to engage the inner surface of the outertubular member 20. FIG. 3G illustrates a pair of seal members 56adjacent one another having triangular cross-sectional shapes. The sealmember 57, shown in FIG. 3H, is elongated with a pointed circumferentialedge configured to engage the inner surface of the outer tubular member20.

The seal members 50-57 may be added at any or all points around thecircumference of the proximal portion 31 of the distal tip 30, dependingon the desired seal. The mold used to make the distal tip 30 may bemodified to include the seal members 50-57, such that the distal tip 30and seal members 50-57 are made from the same flow of material.Alternatively, the seal members 50-57 may be added on after the distaltip 30 is molded using additive technology. Additionally to the sealmember shapes shown in FIGS. 3A-3H, the O-ring shaped seal members 44illustrated in FIG. 2B may also be used on the distal tip 30. The O-ringshaped seal members 44 may be molded as part of the distal tip 30, theO-ring shaped seal members 44 may be arranged in a circumferentialgroove in the proximal portion 31 of the distal tip 30, or the O-ringshaped seal members 44 may be added to the distal tip 30 with adhesive,for example. In further examples, any of the seal member shapesillustrated in FIGS. 3A-3H may be used on the inner member 40.

Any number of seal members 42, 44, 50-57 may be provided on the innermember 40 and/or on the proximal portion 31 of the distal tip 30. WhileFIGS. 2A, 2B and 3A-3H show a single shape and orientation for the sealmembers 42, 44, 50-57, it will be understood that a plurality ofmultiple different shapes of seal members may be present on the innermember 40 and/or on the proximal portion 31 of the distal tip 30. Insome instances, the seal members 42, 44, 50-57 may be disposed on theinner member 40 adjacent the shoulder 43, and on a portion of or theentire proximal portion 31 of the distal tip 30. When multiple sealmembers 42, 44, 50-57 are present, they may extend over a distance of1-20 mm of the inner member 40 and/or distal tip 30, for example.

Additionally or alternatively, the shape and construction of the distalend 22 of the outer tubular member 20 may be altered to create a sealbetween the proximal portion 31 of the distal tip 30 and the outertubular member 20, as shown in FIGS. 4A-4C. In FIG. 4A, the innerdiameter of the outer tubular member 20 decreases at the distal end 22due to addition of material forming a circumferential protrusion 24extending radially inward toward the central longitudinal axis of theouter tubular member 20 into the lumen 21 of the outer tubular member 20at the distal end 22. The protrusion 24 may extend around the entireinner circumference of the outer tubular member 20. The protrusion 24may be made of the same or different material as the outer tubularmember 20. If the protrusion 24 is made of the same material, extrusionproperties could be altered to allow for thickening of the extrusion atthe distal end 22 of the outer tubular member, whereas a differentmaterial may be added post extrusion, or during a different phase of theextrusion process, if desired. The protrusion 24 may be compressible orincompressible. The protrusion 24 may be added in a way that createscurvature, which may allow the protrusion 24 to travel smoothly over thebeveled proximal end 33 of the proximal portion 31 of the distal tip 30despite the decreased inner diameter of the distal end 22 of the outertubular member 20.

In some examples, the outer tubular member 20 may have a taper 26 at thedistal end 22 such that the inner diameter is decreased at the distalend 22 without adding a protrusion or thickening the material of theouter tubular member 20, as shown in FIG. 4B. In other examples, boththe protrusion 24 and a taper 26 may be present at the distal end 22 ofthe outer tubular member, as shown in FIG. 4C. The beveled proximal end33 of the distal tip 30 may aid in moving the tapered distal end 22 ofthe outer tubular member 20 over the proximal portion 31 of the distaltip 30. The distal end 22 of the outer tubular member 20 may be advanceddistally over the angled proximal end 33 and proximal portion 31 of thedistal tip 30 until the distal end 22 abuts the shoulder 35 defined by adistal portion 37 of the distal tip 30 that has a diameter larger thanthe proximal portion 31.

When the outer tubular member 20 is advanced distally over the innermember 40, the protrusion 24 engages the proximal portion 31 of thedistal tip 30, forming a liquid-tight seal between the distal tip 30 andthe outer tubular member 20. In some instances, the diameter of theopening into the lumen 21 of the outer tubular member 20 at the distalend of the outer tubular member 20 in a equilibrium state may be lessthan the outer diameter of the proximal portion 31 of the distal tip 30.In some examples, the protrusion 24 may be rigid, forming the seal basedon a friction fit against the distal tip 30. In other examples, theprotrusion 24 may be compressible, and may be compressed as the outertubular member 20 is advanced distally over the distal tip.

In some examples, a notch or groove 39 may be cut circumferentiallyaround the proximal portion 31 adjacent the shoulder 35 to accept theprotrusion 24 and/or the taper 26 at the distal end 22 of the outertubular member 20, creating a strong mechanical seal, as shown in FIG.4A. In examples with a groove 39 on the proximal portion 31 of thedistal tip 30, a compressible protrusion 24 may return to anon-compressed or equilibrium state when the protrusion 24 is positionedwithin the groove 39.

The protrusion 24 and/or taper 26 at the distal end 22 of the outertubular member 20 may form a releasable friction seal against theproximal portion 31 of the distal tip 30. When the stent is to bereleased, the outer tubular member 20 may be withdrawn proximally fromthe distal tip 30, releasing the seal and opening the liquid-tightchamber 25 for deployment of the stent 60.

The chamber 25 may be filled with liquid via at least one port 70 intothe chamber. In some instances, the inner member 40 may be a hollow tubehaving a lumen extending therein. The port(s) 70 may be made through thewall of the inner member 40 in the stent holding region 41 of the innermember 40 to provide fluid communication from the lumen of the innermember 40 into the chamber 25, as illustrated in FIG. 5A. As shown inFIG. 5A, the inner member 40 may include a plurality of ports 70extending along at least a portion of the length of the stent holdingregion 41 in fluid communication with the lumen of the inner member 40.The port(s) 70 may be in fluid communication with a port 80 at theproximal end of the device 10 via the lumen of the inner member 40. Insome instances, the proximal port 80 may be provided with the handleassembly 14, for example. A fluid source may be coupled to the port 80to infuse fluid through the lumen of the inner member 40 into thechamber 25 through the port(s) 70.

In some examples, an additional channel may be created alongside theinner member 40. In the example shown in FIG. 5B, the additional channelis an additional lumen 72 added to the inner member extrusion. The lumen72 may include a port opening into the chamber 25 at a proximal end ofthe stent holding region 41. The lumen 72 may be in fluid communicationwith the port 80 in the handle assembly 14. In the example shown in FIG.5C, the additional channel is an additional tubular member 74 addedparallel to the inner member 40. The tubular member 74 may be a separateelement that is attached to the inner member 40 with adhesive. Thetubular member 74 may be made of the same or a different material fromthe inner member 40. The tubular member 74 may include a port openinginto the chamber 25 at a proximal end of the stent holding region 41.The tubular member 74 may be in fluid communication with the port 80 inthe handle assembly 14. When a stent stopper 75 is present, an openingor notch 77 may be cut in the stent stopper 75 to allow passage of thetubular member 74 to pass through the stent stopper 75 and into thechamber 25. In another example, the tubular member 74 may be co-extrudedwith the inner member 40.

The injection port 80 may be disposed at the proximal handle assembly 14to allow liquid to be pumped through or alongside the inner member 40and into the chamber 25. In some examples, a pressure release could beadded to the injection port 80 to ease liquid flow into the hydrationchamber 25 and to reduce stagnant liquid in the access channel throughthe inner member 40. The seals between the distal tip 30 and the outertubular member 20 and between the inner member 40 and the outer tubularmember 20 may be sufficient to retain liquid in the chamber 25 from thetime the stent 60 is loaded into the stent holding region 41 of thedevice 10, during shipping, and until the device 10 is inserted into apatient to a delivery site, at which time the seal may be broken as thestent is released from the device and deployed in a body lumen. In someinstances, the injection port 80, the fluid delivery lumen (e.g., thelumen through the inner member 40, the additional lumen 72 or tubularmember 74) and/or the port(s) 70 may include a one-way valve allowingfluid to enter the chamber 25 while preventing retrograde flow of fluidout of the chamber 25.

During stent deployment in which the outer tubular member 20 iswithdrawn proximally relative to the stent 60, the seal between theouter tubular member 20 and the distal tip 30 is broken and liquid willrelease into the body lumen where the stent 60 is being deployed. Asecond catheter may be added down the delivery system presentingnegative pressure to remove liquid before deployment, if desired. If thedevice 10 is used through a working channel of an endoscope, the suctioncapability of the endoscope could be used to collect the liquid as thestent 60 is deployed.

The structural features of the device discussed above may suitably becombined in any combination. In other words, all possible combinationsof the features or structural elements of the present examples arecontemplated, including all features and structural elements describedin conjunction with the drawings.

Use of the device 10 is also contemplated by the present disclosure. Useof the device 10 may include a method for loading a self-expanding stent60 into a delivery and deployment device 10 and delivering the stent 60to a bodily lumen. The method may include radially contracting a stent60 on a delivery device 10, the device 10 including an outer tubularmember 20 having opposed proximal and distal ends, a longitudinal lengthand a lumen, an inner member 40 having opposed proximal and distal endsand a lumen, the inner member 40 slidably disposed within the outertubular member 20, and a distal tip 30 disposed on the distal end of theinner member 40. A stent holding region 41 is provided on the innermember 40 between the distal tip 30 and the shoulder 43 of the innermember 40. A stent 60 is placed over the stent holding region 41 of theinner member 40 and within a hydration chamber 25 defined betweenproximal and distal seals. The distal seal provided between the distaltip 30 and the outer tubular member 20 and the proximal seal providedbetween the outer tubular member 20 and the inner member 40.

The outer tubular member 20 is advanced distally over the stent 60 untilthe distal end 22 engages the proximal portion 31 of the distal tip 30.One or more of the seal members 42, 44 on the inner member 40 may engagethe inner surface of the outer tubular member 20 to form a liquid tightseal and define a proximal end of the chamber 25. One or more of theseal members 50-57 on the proximal portion 31 of the distal tip 30 mayengage the inner surface of the outer tubular member 20 to form a liquidtight seal and define a distal end of the chamber 25. Alternatively, orin addition, the protrusion 24 and/or the taper 26 at the distal end 22of the outer tubular member 20 may engage the proximal portion 31 of thedistal tip 30 to form the liquid tight seal and define the distal end ofthe chamber 25. Once the outer tubular member 20 is advanced distallyand engages the distal tip 30, the chamber 25 is sealed, as shown inFIG. 1. A liquid medium may then be inserted into the chamber 25, viaone or more of the ports 70, additional lumen 72, or tubular member 74.The inner member 40 may have a lumen extending to a proximal end of thedevice 10, with an outlet port for delivering liquid through the innermember 40. In some instances, the injection port 80, the fluid deliverylumen (e.g., the lumen through the inner member 40, the additional lumen72 or tubular member 74) and/or the port(s) 70 may include a one-wayvalve allowing fluid to enter the chamber 25 while preventing retrogradeflow of fluid out of the chamber 25. The stent 60 may be packaged inthis configuration, with the stent 60 secured within the liquid-filledchamber 25. Once the stent 60 has been delivered to a desired locationwithin a patient's body, the method may further include axially movingor sliding the outer tubular member 20 proximally, breaking the sealsand releasing the liquid within the chamber 25 and releasing the stent60 for deployment in a body lumen of the patient.

The materials that can be used for the various components of thedelivery device 10 and the various tubular members disclosed herein mayinclude those commonly associated with medical devices. For simplicitypurposes, the following discussion makes reference to outer tubularmember 20 and inner member 40 and other components of device 10.However, this is not intended to limit the devices and methods describedherein, as the discussion may be applied to other similar devices and/orcomponents of devices or devices disclosed herein.

The outer tubular member 20 and inner member 40 may be formed of a bodycompatible material. Desirably, the biocompatible material is abiocompatible polymer. Examples of suitable biocompatible polymers.include, but are not limited to, polyolefins such as polyethylene (PE),high density polyethylene (HDPE) and polypropylene (PP), polyolefincopolymers and terpolymers, polytetrafluoroethylene (PTFE), polyethyleneterephthalate (PET), polyesters, polyamides, polyurethanes,polyurethaneureas, polypropylene and, polycarbonates, polyvinyl acetate,thermoplastic elastomers including polyether-polyester block copolymersand polyamide/polyether/polyesters elastomers, polyvinyl chloride,polystyrene, polyacrylate, polymethacrylate, polyacrylonitrile,polyacrylamide, silicone resins, combinations and copolymers thereof,and the like. Desirably, the biocompatible polymers includepolypropylene (PP), polytetrafluoroethylene (PTFE), polyethyleneterephthalate (PET), high density polyethylene (HDPE), combinations andcopolymers thereof, and the like. The outer tubular member 20 and theinner member 40 may be made of the same material or they may be made ofdifferent materials.

The outer tubular member 20 and inner member 40 may also have a surfacetreatment and/or coating on their inner surface, outer surface orportions thereof. A coating need not be applied to both the outertubular member 20 and the inner member 40, and individual members may becoated, uncoated, partially coated, and the like. Useful coatingmaterials include any suitable biocompatible coating. Non-limitingexamples of suitable coatings include polytetrafluoroethylene, silicone,hydrophilic materials, hydrogels, and the like. Useful hydrophiliccoating materials include, but are not limited to, alkylene glycols,alkoxy polyalkylene glycols such as methoxypolyethylene oxide,polyoxyalkylene glycols such as polyethylene oxide, polyethyleneoxide/polypropylene oxide copolymers, polyalkylene oxide-modifiedpolydimethylsiloxanes, polyphosphazenes, poly(2-ethyl-2-oxazoline),homopolymers and copolymers of (meth) acrylic acid, poly(acrylic acid),copolymers of maleic anhydride including copolymers of methylvinyl etherand maleic acid, pyrrolidones including poly(vinylpyrrolidone)homopolymers and copolymers of vinyl pyrrolidone, poly(vinylsulfonicacid), acryl amides including poly(N-alkylacrylarnide), poly(vinylalcohol), poly(ethyleneimine), polyamides, poly(carboxylic acids),methyl cellulose, carboxymethylcellulose, hydroxypropyl cellulose,polyvinylsulfonic acid, water soluble nylons, heparin, dextran, modifieddextran, hydroxylated chitin, chondroitin sulphate, lecithin,hyaluranon, combinations and copolymers thereof, and the like.Non-limiting examples of suitable hydrogel coatings include polyethyleneoxide and its copolymers, polyvinylpyrrolidone and its derivatives;hydroxyethylacrylates or hydroxyethyl(meth)acrylates; polyacrylic acids;polyacrylamides; polyethylene maleic anhydride, combinations andcopolymers thereof, and the like. Additional details of suitable coatingmaterials and methods of coating medical devices with the same may befound in U.S. Pat. Nos. 6,447,835 and 6,890,348, the contents of whichare incorporated herein by reference. Such coatings and/or surfacetreatment is desirably disposed on the inside or a portion thereof ofthe outer tubular member 20 to aid, if desired, in loading and/ordeploying of the stent 60.

Additionally, the various components of the devices/systems disclosedherein may include a metal, metal alloy, polymer (some examples of whichare disclosed below), a metal-polymer composite, ceramics, combinationsthereof, and the like, or other suitable material. Some examples ofsuitable metals and metal alloys include stainless steel, such as 304V,304L, and 320LV stainless steel; mild steel; nickel-titanium alloy suchas linear-elastic and/or super-elastic nitinol; other nickel alloys suchas nickel-chromium-molybdenum alloys (e.g., UNS: N06625 such as INCONEL®625, UNS: N06022 such as HASTELLOY® C-22®, UNS: N10276 such asHASTELLOY® C276®, other HASTELLOY® alloys, and the like), nickel-copperalloys (e.g., UNS: N04400 such as MONEL® 400, NICKELVAC® 400, NICORROS®400, and the like), nickel-cobalt-chromium-molybdenum alloys (e.g., UNS:R30035 such as MP35-N® and the like), nickel-molybdenum alloys (e.g.,UNS: N10665 such as HASTELLOY® ALLOY B2®), other nickel-chromium alloys,other nickel-molybdenum alloys, other nickel-cobalt alloys, othernickel-iron alloys, other nickel-copper alloys, other nickel-tungsten ortungsten alloys, and the like; cobalt-chromium alloys;cobalt-chromium-molybdenum alloys (e.g., UNS: R30003 such as ELGILOY®,PHYNOX®, and the like); platinum enriched stainless steel; titanium;combinations thereof; and the like; or any other suitable material.

Some examples of suitable polymers may include polytetrafluoroethylene(PTFE), ethylene tetrafluoroethylene (ETFE), fluorinated ethylenepropylene (FEP), polyoxymethylene (POM, for example, DELRIN® availablefrom DuPont), polyether block ester, polyurethane (for example,Polyurethane 85A), polypropylene (PP), polyvinylchloride (PVC),polyether-ester (for example, ARNITEL® available from DSM EngineeringPlastics), ether or ester based copolymers (for example,butylene/poly(alkylene ether) phthalate and/or other polyesterelastomers such as HYTREL® available from DuPont), polyamide (forexample, DURETHAN® available from Bayer or CRISTAMID® available from ElfAtochem), elastomeric polyamides, block polyamide/ethers, polyetherblock amide (PEBA, for example available under the trade name PEBAX®),ethylene vinyl acetate copolymers (EVA), silicones, polyethylene (PE),Marlex high-density polyethylene, Marlex low-density polyethylene,linear low density polyethylene (for example REXELL®), polyester,polybutylene terephthalate (PBT), polyethylene terephthalate (PET),polytrimethylene terephthalate, polyethylene naphthalate (PEN),polyetheretherketone (PEEK), polyimide (PI), polyetherimide (PEI),polyphenylene sulfide (PPS), polyphenylene oxide (PPO), polyparaphenylene terephthalamide (for example, KEVLAR®), polysulfone,nylon, nylon-12 (such as GRILAMID® available from EMS American Grilon),perfluoro(propyl vinyl ether) (PFA), ethylene vinyl alcohol, polyolefin,polystyrene, epoxy, polyvinylidene chloride (PVdC),poly(styrene-b-isobutylene-b-styrene) (for example, SIBS and/or SIBS A),polycarbonates, ionomers, biocompatible polymers, other suitablematerials, or mixtures, combinations, copolymers thereof, polymer/metalcomposites, and the like. In some embodiments the sheath can be blendedwith a liquid crystal polymer (LCP). For example, the mixture cancontain up to about 6 percent LCP.

In at least some embodiments, portions or all of the delivery device 10and/or other components of delivery system may be doped with, made of,or otherwise include a radiopaque material. Radiopaque materials areunderstood to be materials capable of producing a relatively brightimage on a fluoroscopy screen or another imaging technique during amedical procedure. This relatively bright image aids the user of thedelivery device 10 in determining its location. Some examples ofradiopaque materials can include, but are not limited to, gold,platinum, palladium, tantalum, tungsten alloy, polymer material loadedwith a radiopaque filler, and the like. Additionally, other radiopaquemarker bands and/or coils may also be incorporated into the design ofthe delivery device 10 to achieve the same result.

It should be understood that this disclosure is, in many respects, onlyillustrative. Changes may be made in details, particularly in matters ofshape, size, and arrangement of steps without exceeding the scope of thedisclosure. This may include, to the extent that it is appropriate, theuse of any of the features of one example embodiment being used in otherembodiments. The invention's scope is, of course, defined in thelanguage in which the appended claims are expressed.

What is claimed is:
 1. A stent delivery system comprising: an innermember having a distal tip, and a stent holding region proximal of thedistal tip, an outer tubular member slidingly disposed over the innermember; a liquid-tight sealed chamber located radially between an outersurface of the stent holding region of the inner member and an innersurface of the outer tubular member; wherein the liquid-tight sealedchamber is defined between a first seal member at a proximalmost extentof the liquid-tight sealed chamber and a second seal member at adistalmost extent of the liquid-tight sealed chamber; and a stentdisposed in the liquid-tight sealed chamber between the first sealmember and the second seal member.
 2. The stent delivery system of claim1, wherein the first seal member is disposed between the inner memberand the outer tubular member proximal of the stent holding region. 3.The stent delivery system of claim 2, wherein the second seal member isdisposed between the distal tip and the outer tubular member.
 4. Thestent delivery system of claim 1, wherein the inner member includes alumen with at least one port configured to deliver liquid to theliquid-tight sealed chamber.
 5. The stent delivery system of claim 4,wherein the at least one port includes a plurality of ports extendingfrom the lumen into the liquid-tight sealed chamber, the plurality ofports disposed along the stent holding region.
 6. The stent deliverysystem of claim 1, wherein the second seal member includes at least onecircumferential protrusion disposed on an inner surface of the distalend of the outer tubular member.
 7. The stent delivery system of claim6, wherein the distal tip includes a groove configured to receive theprotrusion.
 8. The stent delivery system of claim 1, wherein the outertubular member includes a distal end configured to engage the distaltip.
 9. The stent delivery system of claim 1, wherein the stent isradially compressed between the inner member and outer member along thestent holding region.
 10. The stent delivery system of claim 1, whereinthe first seal member is disposed on an outer surface of the innermember.
 11. The stent delivery system of claim 10, wherein the secondseal member is disposed on an inner surface of the distal end of theouter tubular member.
 12. The stent delivery system of claim 1, whereinthe second seal member is disposed on an inner surface of the distal endof the outer tubular member.
 13. A stent delivery device comprising; aninner member having a distal tip, a stent holding region, and at leastone first seal member disposed on an outer surface of the inner memberproximal of the stent holding region; and an outer tubular memberslidingly disposed over the inner member, the outer tubular memberhaving a distal end configured to engage the distal tip; wherein atleast one of the distal tip and the distal end of the outer tubularmember includes at least one second seal member, wherein a combinationof the first and second seal members defines a liquid-tight sealedchamber surrounding the stent holding region.
 14. The stent deliverydevice of claim 13, wherein the inner member includes a lumen extendingto at least one port opening into the liquid-tight sealed chamber. 15.The stent delivery device of claim 14, wherein the at least one portincludes a plurality of ports disposed along the stent holding region.16. The stent delivery system of claim 13, further comprising a stentdisposed in the liquid-tight sealed chamber between the at least onefirst seal and the at least one second seal.
 17. A stent delivery systemcomprising: an outer tubular member having a lumen extendingtherethrough; an inner member having a distal tip and a stent holdingregion proximal of the distal tip, the inner member slidingly disposedthrough the lumen of the outer tubular member with the outer tubularmember surrounding the stent holding region while a distal end of theouter tubular member engages the distal tip; a first seal memberdisposed between the inner member and the outer tubular member proximalof the stent holding region; and a second seal member disposed betweenthe inner member and the outer tubular member distal of the stentholding region; wherein a combination of the first and second sealmembers defines a liquid-tight sealed chamber therebetween andsurrounding the stent holding region; wherein inner member includes alumen extending to at least one port in fluid communication with theliquid-tight sealed chamber, the at least one port disposed along thestent holding region; and a stent disposed within the liquid-tightsealed chamber radially between the inner member and the outer tubularmember, the stent positioned between the first seal member and thesecond seal member along the stent holding region.
 18. The stentdelivery assembly of claim 17, wherein the first seal member is disposedon an outer surface of the inner member.
 19. The stent delivery assemblyof claim 18, wherein the second seal member is disposed on an innersurface of the distal end of the outer tubular member.
 20. The stentdelivery assembly of claim 17, wherein the at least one port includes aplurality of ports disposed along the stent holding region.